Cutting off mechanism for tube and bag making machinery



June 9, 1936. 2,043,554

TUBE AND BAG MAKING IVIAG'HINER.'r

Filed March so, 1934 A.. PoTDEvlN CUTTING OFF MECHANISM FOR Patente-d June 9, 1936 PATENT oFFiCE l 2,043,554 CUTTING ont` MEcIIANI'sM Foa TUBE AND BAG MAKING MAcIImEaY Adolph Potdevin, Garden City, Long Island, N. Y.,

assigner to Potdevin Machine Company, Brooklyn, N. Y., acorporation oi.' New York Application March 30, 1934, Serial No. 718,153

3 Claims.

This invention is directed to an .improvement in cut off mechanism for tube and bag making machinery.

In certain types of cut oiI mechanism heretofore used in this type of apparatus it is customary to feed the materialwhich is in the form of a tubular web along the upper and lower sides of a fixed plate. A stationary cut off member or knife is located above thisA plate and a striker bar is rotated upwardly from beneath the tube so as to sever the lowerwall of the tube along the end of the fixed plate, the upper wall of the tube being severed along theedge of the knife. The knife is usually set slightly back of the end of thexed plate, so as to provide a flap on one wall of the tube.

'inasmuch as the xed plate is necessarily of light material it has considerable spring to it with the result' that in the' cutting of! operation it is moved upwardly and strikes the edge of the knife. dulling the same.

In handling paper, when making paper bags A and tubes, the paper 4is relatively heavy so as to somewhat cushion the blow. In recent years with the extensive use of glassine, cellophane and such materials which tear very readily this drawback has become very objectionable inasmuch as the cut off knife must be kept sharp for satisfactory results, and the present invention provides means for preventing raising of the flxed plate during the ycutting oil orLsevering operation so that contact of the plate with the edge of the knife is avoided.

In the accompanying drawing: Fig. 1 is a sectional side elevational view of an embodiment of my invention;

Fig. 2 is a view similarto Fig.- cutting oifmechanism in operation; and

Fig. 3 is a plan view. Referring to the drawing in detail, I and 2 designate the feed rollers by which the tubular web 3 is advanced through the machine to the cutting oit mechanism. During the cutting of! operation the tube is retarded in itsadvance by pinch rolls 4 and 5 running at a lower peripheral speed than the feed rollers to create slack in thematerial during this period. 'I'hls slack is controlled during the cutting oiI operationby rollers 6 4and 1 located intermediate the cut on station and the pinch rolls. This mechanism,

A however, constitutes the subject matter of my I'snowmg the (c1. ca -33) 1 plate s in the pain of the album' material, this l material passing above and below the plate and shown in the drawing. This plate is of thin light metal. Above the fixed plate 8 and disposed slightly 5 to the rear of the end of the plat`e, depending upon the length of the'wall ap desired, is a fixedknife 9 mounted on a suitable bracket l0. Cooperating with the plate 8 and knife 9 is a striker bar Il. (This bar is shown as mounted on a 10 driven shaft I2 disposed parallel to the travel of 4the tubular material 3 so that the bar is rotated upwardly from beneath the advancing material to intersect the material. This method of mounting and driving the striker bar may he varied as 15 will be appreciated within the` spirit and scope y of my invention.

the hired plate 8 sufficiently to permit the wall 20 of the tubular material 3 to pass therebetween.

With this mechanism in operation the material 3 is continuously advanced, and at a predetermined instant the striker bar Il is moved upwardly as shown by a comparison of Figs. 1 25 and 2, carrying the material 3 upwardly to sever the lower wall thereof .across the end of the xed plate 8 and the upper wall against the edge of the knife 9. During the severing of the lower wall it will be appreciated tension is ex- 8G erted in an upward direction on the plate 8, and while this plate is of springy material, light metal, it is positively prevented from contacting with the knife 9 to dull the same, by the stop plate l2. V315 It will be seen, therefore, that my invention provides an arrangement particularly useful in working with glassine, cellophane and similar materials in that the knife 9 which is provided for cutting through one wall `of the' tube Amaterial 40j is kept out of contact with the plate 8 and ing of the knife prevented. Y l

What I claim isz- 1. Cut-off mechanism for bag and tube ing machines comprising in combination a relatively thin xed plate in the path of the tubular material being handled and disposed so as to telescoped thereby, a movable member out of the plane of one face of said plate, a xed knife out of the plane vof the other face of the fixed plate, said movable member being movable in a direc,- tion to divide one wall of the tube across the end of the xedplate and the opposite wall of the tube acrossl the edge of the said knife, and means intermediate the said fixed plate and xed dullthe face of the plate out of contact with each. other at all times.

2. Cut-off mechanism for bag and tube making machines comprising in combination a relatively thin fixed plate inthe path of the tubular material being handled and disposed so as to be telescoped thereby, a movable member out of the plane of one face of said xed plate, a xed knife out of the plane of the other face of the xed plate, said movable member being movable in a direction to divide one wall of the tube across the end of the xed plate `and the opposite Wall across the edge of the saidknife, and means disposed at the knife side of the xed plate intermediate it and said knife and spaced from the iixed plate lsniciently to permit the tubular material to pass between it and the ixed plate, for maintaining the knife and xed plate out of contact with each other at all times.

p 2,043,554 n knife for maintaining the edge of said knife and 3. Cut-oil mechanism for bag and tube making m comprising in combination a relatively thin xed metal plate in the path. of the tubular material being handled, said plate being so disposed as to be telescoped by the material, a striker bar adapted to engage one wall oi the tubular material as the same leaves the ried plate to sever or divide said Wall across the end of the fixed plate, a ixed knife disposed out of the plane of one face of the ixed plate and in such position that the undivided wall of the tubular material on continued movement of the striker bar is moved into engagement with the edge of said knife to sever or divide the remaining wall of the tubular material, and a stop member interposed between said knife and said fixed plate maintaining the xed plate and knife out of contact with each other at all times.

ADoLPH Po'rnnvm. 20 

